Skip the auto shop - Our mechanics make house calls

Q: How Can I Tell If My Car Battery Needs Replacing?

asked by on

How can I tell if my car battery needs replacing?

A battery needs to be replaced when it can no longer support the electrical and starting system of the vehicle. How will you know this? The most common first signs that a battery is starting to go bad may not be obvious at first. You may start to see an intermittent dim in your lights when you turn on an electrical system like an AC blower or interior light when you are at idle. Your radio light may dim when the AC compressor cycles on and off. These may be some first signs your battery is getting weak.

As your battery ages, it uses up its internal battery lead plates and will get weaker as time goes by. Depending on the make and model of battery you have, it may last anywhere from two years to five or six. Most batteries will last about three years or more. Even though they last this long, they will get weaker over time and if you are pushing the battery and charging to the limits of its capacity now, it may not last too much longer before showing major signs of needing replacement.

The major signs of a battery needing replacement is excessive corrosion buildup on top of the battery and its posts. After this, you will have a slow cranking engine during startup. Then you may notice intermittent no-crank conditions and have to jumpstart the vehicle after it sits for a couple of days. It cannot hold a charge for that long of a period.

Once you start to have these kind of problems you will need to have the battery replaced and the cables serviced. If you do not and continue to drive it this way you will start to put a bigger and bigger strain on the alternator. This in turn will cause the alternator to fail and then you will have a battery and alternator to replace. Once the battery is replaced and the cables replaced or cleaned as needed, the charging system should be tested to make sure there has been no damage to it. The alternator will need to have a good battery to be properly tested.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Lights on dash are malfunctioning and sensors like airbags are tripped.

Unless the incident which knocked your mirror off was also the "pothole from hell", there is not likely a connection. You don't mention what year or model for your GMC, but GM supplied a digital dash for late model GMC...

Q: Air conditioner clutch doesn't engage

Hello there, a few different faults can cause the AC clutch not to engage on your 1998 Nissan 200SX. The most common would be the refrigerant is low, AC high pressure switch, AC clutch failure, or lack of voltage to...

Q: Battery jump reverse connectors

Hey there, thanks for writing in about your 2013 Kia Fote Koup. Fuses are in place to protect wiring and components from failure. By connecting the cables in reverse direction you created a surge in amperage, and the flow of...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.